The present invention relates to a mobile device for an X-ray apparatus, and more particularly, the invention relates to an X-ray apparatus useful for a circuit examination by a doctor, wherein an X-ray tube holding section moves vertically or up and down along a rotatable column disposed on a base or truck.
A mobile type X-ray apparatus for a circuit examination by a. doctor in a conventional cordless condenser type is shown in FIG. 2. In the mobile type X-ray apparatus, a controller 13 is placed on a mobile base or truck 1, and a column 3 for suspending and holding an X-ray tube 10 is disposed upright or vertically.
The controller 13 placed on the mobile truck 1 is provided with a high-voltage transformer and a condenser or capacitor. A control circuit of the controller 13 is systemized, and an automatically programmed one-touch system is frequently used for photographing operation. It is important for the mobile type X-ray apparatus for a circuit examination by a doctor to be small and light-weight, so that the mobile type X-ray apparatus is moved to a bedroom, a technician room, an operation room, a children room, an X-ray room, an infant room, or the like in a hospital so as to take an X-ray photographing easily at these sites.
The X-ray tube 10 in the mobile type X-ray apparatus can be positioned at any places as an advantage of a mobile type. Namely, the column 3 is freely rotatable as described later, and the X-ray tube 10 is held by the column 3 to be freely movable in a vertical direction. More specifically, the X-ray tube 10 is held at a distal end of a side arm 11 disposed at a carriage 7 attached perpendicularly thereto, and the carriage 7 ascends and descends along the column 3. The X-ray tube 10 can be rotated at the distal end of the side arm 11 in a direction perpendicularly to an axial direction of the tube.
Namely, the hollow column 3 is vertically disposed at a rotational shaft or shaft portion 4 held by a bearing portion 2 provided on the mobile truck 1. On the other hand, the carriage 7 and the side arm 11 ascend and descend along the hollow column 3. A counter weight 8 is hung from one end of a wire 9 to be movable up and down. A pulley 6 is provided at an upper portion of the hollow column 3, and the other end of the wire 9 extending through the pulley 6 is connected to the carriage 7. The weight of the counter weight 8 and weight of the X-ray tube 10 with a holding section therefor, i.e. the carriage 7 and the side arm 11, are set to be the same so as to be balanced. Further, the side arm 11 can be retracted and extended to move the X-ray tube in the front and rear directions.
As described above, the arm portion, i.e. side arm 11, which includes a supporting system and a rotating system for the X-ray tube 10 and is extended and retracted in the horizontal direction, is designed to have a mechanism which allows the side arm 11 to vertically move along the column 3 smoothly with a balanced condition. Also, the side arm 11 or the arm portion is designed so that a collimator, i.e. X-ray emission port, of the X-ray tube 10 can face a part to be photographed of an examinee, i.e. patient, in any directions and in any spatial positions.
Rubber tires are attached to the mobile truck 1, and the mobile truck 1 is designed such that it can freely move into and out of a patient's room, an operation room and an elevator.
Further, the mobile truck 1 includes a braking system, a cassette box, and accessory devices.
The conventional mobile type X-ray apparatus is structured as described above. However, in order to move the X-ray tube 10 up and down smoothly along the column 3 while being well-balanced, the counter weight 8 corresponding to the weight of the X-ray tube 10 is stored in a hollow portion of the column 3, so as to prevent collision with other members which are hung outside the column 3. Since it is necessary for the counter weight 8 to be disposed in a limited inner space of the column 3, the counter weight is required to have a small volume and large specific gravity. Thus, lead is generally used for the counter weight, but it is not preferable to use lead from an environmental viewpoint. When the counter weight 8 is made of iron, in order to hold the large volume of iron corresponding to the volume of the counter weight, it is necessary to make the column 3 thicker or higher. Also, if the thickness and the height of the column are maintained as in the conventional one, there is a problem that the counter weight 8 is extended longer, so that a stroke of the up-and-down movement of the X-ray tube 10 becomes shorter for the length of an extended portion of the counter weight 8.
The present invention has been made in view of the aforementioned problems, and an object of the present invention is to provide a mobile device for an X-ray apparatus, which can be made compact without changing the substantial portion of the apparatus.
Another object of the invention is to provide a mobile device for an X-ray apparatus as stated above, wherein a counter weight for the apparatus can be made of a material suitable for an environment.
Further objects and advantages of the invention will be apparent from the following description of the invention.